1. Field of the Invention
The present invention relates to a method of purchasing refill units, and more specifically, to a method for purchasing refill units online and using the refill units to execute local software.
2. Description of the Prior Art
Due to the increasing popularity of the Internet, many business transactions can now be performed online. For example, some software packages can perform a paid function a certain amount of times before an original number of purchased units has been exhausted. Every time the paid function is executed, the number of remaining purchased units is decreased by one. The purchased units may be included with the original software package, or may be bought separately by a user of the software package. Nevertheless, when all of the purchased units have been exhausted, the user must purchase refill units in order to keep using the paid function of the software package.
The Internet has become a preferred medium for purchasing refill units due to the speed and convenience offered. When purchasing refill units, the user will fill out an order form on a secure web site to indicate a number of refill units to be purchased and to provide billing information such as a credit card number. After the purchase has been verified, the web site will display a serial number that the user may use to receive the purchased refill units. The user can then enter the serial number into a user interface of the software program in order to increase the available number of purchased units. A new total of the purchased units will be equal to the previous total plus the number of refill units purchased.
Unfortunately, the serial number is susceptible to fraudulent use. For instance, the user who purchased refill units may copy down the serial number displayed on the secure web site and illegally share this serial number with friends or may even post the serial number on the Internet for all to see. Therefore, there is a need for a new method of purchasing refill units online.